class A{

  age = 10;
  sayA(){
    console.log("sayA in A");
  }

  getage(){
    console.log("age " + this.age);
  }
}


var a= new A();
a.sayA();
a.getage();

class B extends A{

  age = 99;

  sayA(){
    console.log("sayA in B");
  }
  
  rep(a){
    console.log("rep " + a);
  }
}


var b = new B();
b.sayA();
b.getage();
b.rep("aaa");
b["rep"]("bbb");
